Cursor Talk to Figma MCP

Instructions

Implementation Reference

• src/talk_to_figma_mcp/server.ts:2961-3006 (registration)

  MCP tool registration for 'join_channel' including inline handler and schema definition.

  server.tool(
    "join_channel",
    "Join a specific channel to communicate with Figma",
    {
      channel: z.string().describe("The name of the channel to join").default(""),
    },
    async ({ channel }) => {
      try {
        if (!channel) {
          // If no channel provided, ask the user for input
          return {
            content: [
              {
                type: "text",
                text: "Please provide a channel name to join:",
              },
            ],
            followUp: {
              tool: "join_channel",
              description: "Join the specified channel",
            },
          };
        }
  
        await joinChannel(channel);
        return {
          content: [
            {
              type: "text",
              text: `Successfully joined channel: ${channel}`,
            },
          ],
        };
      } catch (error) {
        return {
          content: [
            {
              type: "text",
              text: `Error joining channel: ${error instanceof Error ? error.message : String(error)
                }`,
            },
          ],
        };
      }
    }
  );

• src/talk_to_figma_mcp/server.ts:2967-3005 (handler)

  The main handler function for the 'join_channel' tool. Validates input, calls joinChannel helper, and returns success/error response.

  async ({ channel }) => {
    try {
      if (!channel) {
        // If no channel provided, ask the user for input
        return {
          content: [
            {
              type: "text",
              text: "Please provide a channel name to join:",
            },
          ],
          followUp: {
            tool: "join_channel",
            description: "Join the specified channel",
          },
        };
      }
  
      await joinChannel(channel);
      return {
        content: [
          {
            type: "text",
            text: `Successfully joined channel: ${channel}`,
          },
        ],
      };
    } catch (error) {
      return {
        content: [
          {
            type: "text",
            text: `Error joining channel: ${error instanceof Error ? error.message : String(error)
              }`,
          },
        ],
      };
    }
  }

• src/talk_to_figma_mcp/server.ts:2964-2966 (schema)

  Zod input schema for the tool, defining the 'channel' parameter.

  {
    channel: z.string().describe("The name of the channel to join").default(""),
  },

• src/talk_to_figma_mcp/server.ts:2883-2896 (helper)

  Helper function that sends the WebSocket 'join' message to the socket server (src/socket.ts) to join the specified channel.

  async function joinChannel(channelName: string): Promise<void> {
    if (!ws || ws.readyState !== WebSocket.OPEN) {
      throw new Error("Not connected to Figma");
    }
  
    try {
      await sendCommandToFigma("join", { channel: channelName });
      currentChannel = channelName;
      logger.info(`Joined channel: ${channelName}`);
    } catch (error) {
      logger.error(`Failed to join channel: ${error instanceof Error ? error.message : String(error)}`);
      throw error;
    }
  }